Assertion (A): In plants there are no specialised respiratory organs.
Reason (R): Plants do not require great demands of gaseous exchange.

Options

A. Both A and R are true, and R is correct explanation of the assertion.
B. Both A and R are true, but R is not the correct explanation of the assertion.
C. A is true, but R is false.
D. A is false, but R is true.

Explanation

To analyze the given assertion and reason, we can break down the steps as follows:

### Step 1: Understand the Assertion
**Assertion (A)** states that "In plants there are no specialized respiratory organs." This means that unlike animals, which have specific organs like lungs or gills for respiration, plants do not have such specialized structures.

### Step 2: Understand the Reason
**Reason (R)** states that "Plants do not require great demands of gaseous exchange." This implies that the process of respiration in plants does not need to be as intensive as in animals, which is why they do not have specialized organs for this purpose.

### Step 3: Analyze the Relationship between Assertion and Reason
To determine if the reason supports the assertion, we need to consider how plants perform respiration. Plants primarily exchange gases through structures called stomata, which are small openings on the surface of leaves. They also utilize lenticels on stems for gas exchange. The gaseous exchange in plants is sufficient for their needs, particularly because they produce oxygen during photosynthesis.

### Step 4: Conclusion
Since the assertion is true (plants do not have specialized respiratory organs) and the reason provided is also true (plants do not have great demands for gaseous exchange), we can conclude that the reason correctly explains the assertion.

### Final Answer
Both the assertion and the reason are true, and the reason is a correct explanation of the assertion.

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